MULTIPLE SLEEP LATENCY TEST (MSLT)
Narcolepsy is a condition popularly characterized by sudden episodes of sleep attacks during normal daytime activities. As funny as it is portrayed in movies, narcolepsy can be a dangerous and debilitating disease - especially for those who drive for a living.
However, frequent unwanted naps are not only a sign of narcolepsy. Other sleep disorders such as obstructive sleep apnea, delayed sleep phase syndrome, periodic limb movements, and parasomnias can also cause severe daytime drowsiness.
A multiple sleep latency test is the only way to distinguish narcolepsy from other types of sleep disorders.
This test begins with an in-lab polysomnogram in order to ensure overnight sleep quality and quantity prior to assessing daytime sleepiness. The MSLT is conducted by a daytime technician who directs a series of five 20-minutes naps at 2-hour intervals throughout the day. These naps are completed in a sleep-inducing environment - lying flat in bed, lights out, eyes closed, and with minimal noise - to test if a patient can fall asleep outside of normal sleep hours, how quickly they can do so, and what stages of sleep are achieved.
See if you are excessively sleepy by taking the Epworth Sleepiness Scale (click below) or learn more about narcolepsy.